This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
| n | a(n) |
|---|---|
| 4 | 4 |
| 5 | 23 |
| 6 | 107 |
| 7 | 464 |
| 8 | 1950 |
| 9 | 8063 |
| 10 | 33033 |
| 11 | 134576 |
| 12 | 546312 |
| 13 | 2212550 |
| 14 | 8946454 |
| 15 | 36134656 |
| 16 | 145831270 |
| 17 | 588199815 |
| 18 | 2371435125 |
| 19 | 9557736480 |
| 20 | 38511326040 |
| 21 | 155143873170 |
| 22 | 624899673690 |
| 23 | 2516678580000 |
| 24 | 10134353299980 |
| 25 | 40805797511622 |